Hongnuo (shenyang) General Machinery Co., Ltd. is one of the most reliable manufacturers and suppliers of electronic water flow switch in China. Welcome to buy high quality electronic water flow switch at competitive price from our factory. We also accept customized orders.

What problem does this solve

HNF10-A

Left ：❌ Paddle flow switches get stuck, wear out, and get tangled by debris.
Right ：✅ HNF10-A has no moving parts in the flow path. Nothing to jam. Nothing to wear.

Product specs at a glance

Spec	Value
Media	Water (including deionized) / Oil (hydraulic, lubricating, diesel, etc.)
Probe material	316L stainless steel
Housing material	304 stainless steel
Pressure rating	1.6 MPa
Output	NPN or PNP (selectable)

Three probe lengths available: standard (DN15–DN100), long (DN100–DN350), small (DN8–DN10).

>View all specifications

How it works

hnf10-a prn

Heated NTC sensor inside the probe. Static fluid = heat accumulates, temperature difference is small. Moving fluid = heat is carried away, temperature difference increases. The switch triggers when flow stops.

Where to use

Machine tool coolant lines.

Pump station discharge lines.

High-temperature industrial equipment cooling system

Semiconductor Cooling System.

installation precautions

Insertion installation. Probe tip must reach pipe centre for best sensitivity.
Recommended straight pipe section: ≥5× pipe diameter upstream.
Do not install on pipe bottom (sediment accumulation).
Tightening torque for thread connection: 20–30 N·m.
LED indicator visible from top after installation – check before final fix.

HNF10-A Thermal Flow Switch
Specific Parameters	Value / Description
Measurement Principle	Thermal flow switches typically include a heating element and at least one temperature sensor (or use the heating element as a temperature detection element as well). Their operation relies on the cooling effect of fluid flow on heat: No flow: The heat generated by the heating element is mainly dispersed through natural convection and conduction, causing the temperature detected by the sensor to be higher. With flow: The flowing fluid accelerates the loss of heat, causing the sensor temperature to drop. The greater the flow, the faster the heat dissipation, and the more pronounced the temperature change. By detecting temperature or heat changes, it can be determined whether the fluid is flowing or if the flow has reached a set threshold.
Nominal Diameter Range	Thread G1/2", G1/4", others customizable
Wetted Parts Material	316L
Connection Method	Threaded Connection
Maximum Measurement Error
Measurement Range	0.3-0.5 meters per second
Maximum Process Pressure	1.6MPa
Medium Temperature Range	-10°C to 80°C
Ambient Temperature Range	-10°C to 80°C
Transmitter Housing Material	Unrestricted
Display/Operation	No display
Inputs
Outputs	NPN PNP
Power Supply	24VDC 2W
Certificate
Functional Safety	Functional safety follows the IEC 61508 standard, allowing its use in safety applications as stipulated by the IEC 61511 standard.
Ordering Information